In recent years, lifestyle related diseases including obesity and diabetes are increasing owing to the world-wide tendency to excessive energy intake (increase in the intake of fats or sucrose) and insufficient exercise. Considering such a social background, a measure for preventing or ameliorating obesity or diabetes is very important.
One of the methods proposed commonly by nutritionists in order to prevent or ameliorate obesity or diabetes is intake of a low calorie diet or low fat diet. It has recently been reported that water insoluble food fiber such as wheat bran, water soluble food fiber such as indigestible dextrin, and digestion resistant starch such as high amylose starch have a lipid excretion accelerating action (Am. J. Clin. Nutr., 31 (10 Suppl), S21-S29(1978)), a sugar absorption inhibitory action (Endocrine Journal, 68(6), 623-35(1992)), and a blood neutral fat level lowering action (Am. J. Clin. Nutr. 49(2), 337-44(1989)), or a glucose tolerance improving action (Acta Paediatr Hung 1985 26(1):75-7, J Endocrinol 1995 144(3):533-8, Am J Clin Nutr 1989 49(2):337-44), respectively. It is suggested that they are therefore effective for the prevention/amelioration of obesity, or prevention/amelioration of diabetes.
A drastic rise in the after-meal blood lipid level is presumed to accelerate accumulation of fats, so that suppression of after-meal hyperlipidemia (a rise in blood triglyceride level) is also a very important approach for the prevention/amelioration of obesity. In recent years, xanthan gum and propylene glycol alginate (JP-A-1993-186356), and chitosan (JP-A-1991-29017) have been reported as a safe and effective lipid absorption inhibitor.
The above-described low calorie diet or low fat diet temporarily brings about an effect on weight decrease, but after intake of it for a prolonged time, it comes to be refused because of a monotonous taste of the food constituting such a diet. It is therefore difficult to continue consuming such a diet. The above-described conventional food materials such as water insoluble food fiber, water soluble food fiber and digestion resistant starch do not exhibit the above-described physiological actions until they are administered for a long period of time at a high dosage. Even if they exhibit these physiological actions, their effect for inhibiting obesity has not yet been confirmed. Moreover, when food or beverage is prepared using them, the original texture of the food or beverage such as appearance, taste, touch or smoothness tends to be damaged and it is therefore difficult to incorporate a sufficient amount of them in food. This leads to problems such as limited application range and difficulty in intake of such food or beverage for a long period of time.
A hydroxypropylated starch is known to have high transparency, excellent film forming property, and high low-temperature storage stability and lyophilization/thawing stability. And use of it for food is approved by FDA in USA (Journal of Home Economics of Japan, 49(9), 985-992(1998)).
It is however unknown that hydroxypropylated starches have an effect of preventing/lessening the onset of lifestyle related diseases such as obesity and diabetes.